Both SMILE Pro and ReLEx SMILE are flapless, bladeless, touchless laser eye surgeries through a 2–4mm keyhole incision. Both preserve corneal structure better than LASIK, carry significantly lower dry eye risk, and produce comparable long-term visual outcomes — published series confirm 98–99% of patients achieving 20/20 or better for myopia with either procedure. The clinical differences between them are real, but differences of degree, not kind. This guide explains those differences using the specific published data that actually matters for your decision.
Key Takeaways
- SMILE Pro uses ZEISS VISUMAX 800 at 2 MHz — lenticule creation in 7–10 seconds per eye. ReLEx SMILE uses VISUMAX 500 at 500 kHz, taking 25–30 seconds per eye.
- Published data: suction loss in ReLEx SMILE ~0.5% (65% of cases occurring after 10 seconds of lenticule creation). SMILE Pro’s higher speed significantly reduces suction exposure time and suction loss risk.
- SMILE Pro adds Smart Robotic Assistance and AI-guided centration — automatically compensating for micro-rotations. ReLEx SMILE does not have these systems.
- SMILE Pro now treats hyperopia up to +6D (CE-marked). ReLEx SMILE is approved for myopia only (up to -10D with astigmatism ≤-5D; FDA 2018).
- Both procedures produce 98–99% 20/20 or better for myopia (published series). The advantage of SMILE Pro is procedural — faster, more precise — not a difference in final visual acuity for the same prescription.
- Both carry significantly less dry eye than flap-based LASIK — preserving the subbasal corneal nerve plexus through the flapless approach (PMC meta-analyses confirm).
SMILE Pro vs ReLEx SMILE — Full Comparison
| Factor | SMILE Pro (VISUMAX 800) | ReLEx SMILE (VISUMAX 500) |
|---|---|---|
| Laser platform | ZEISS VISUMAX 800 — CE mark 2022; introduced at Visual Aids Centre Delhi 2023 | ZEISS VISUMAX 500 — FDA approved 2018; clinical use since 2011 (CE mark) |
| Pulse frequency | 2 MHz (2,000 kHz) | 500 kHz — 4× slower than SMILE Pro |
| Lenticule creation time | 7–10 seconds per eye | 25–30 seconds per eye |
| Suction loss rate | Significantly reduced — shorter suction exposure window | ~0.5% (published data; 65% of cases after 10 seconds of lenticule creation) |
| Robotic assistance + AI | Smart Robotic Assistance + AI centration — auto-compensates for micro-rotations | Not available — manual positioning |
| Treatment range | Myopia up to -10D; astigmatism up to -5D; hyperopia up to +6D (CE-marked) | Myopia up to -10D; astigmatism up to -5D; no hyperopia indication |
Published Clinical Outcomes — SMILE Pro vs ReLEx SMILE vs Femto-LASIK
The data that matters most — published clinical series compared across all three procedures:
| Outcome Metric | SMILE Pro | ReLEx SMILE | Femto-LASIK (Benchmark) |
|---|---|---|---|
| % achieving 20/20 or better | 98–99% (VISUMAX 800 published series) | 98–99% (published; 12+ year outcomes across multiple centres) | 99.5% (2016 Modern LASIK Outcomes study; cited AAO 2024) |
| Post-op dry eye (OSDI severity) | Less than LASIK; comparable to ReLEx SMILE (PMC meta-analyses) | Less than LASIK — OSDI MD −4.82 vs LASIK at 3 months (Fudan University EENT Hospital study, PMC) | Higher than both SMILE variants — flap severs corneal nerves significantly |
| Suction loss rate | Significantly lower than ReLEx — shorter suction window | ~0.5% (published; 65% of cases occurring after 10 seconds) | N/A — no suction cup in LASIK procedure |
| Corneal nerve recovery (6 months) | Higher preservation than LASIK — no flap cuts nerve plexus | Higher preservation than LASIK — established in published corneal confocal microscopy studies | Lower — flap creation severs the subbasal nerve plexus significantly |
| Biomechanical strength | Superior to LASIK — no flap; published PMC data confirms stronger post-procedure corneal integrity | Superior to LASIK — same mechanism; comparable to SMILE Pro (OR=0.50 vs LASIK for dry eye, Fudan study) | Lower — flap creation reduces corneal tensile strength |
Technology: VISUMAX 800 vs VISUMAX 500 — What Changed
| Feature | VISUMAX 800 (SMILE Pro) | VISUMAX 500 (ReLEx SMILE) | Clinical Impact |
|---|---|---|---|
| Pulse frequency | 2 MHz | 500 kHz | SMILE Pro delivers lenticule 3–4× faster — less suction exposure, reduced patient stress |
| Smart Robotic Arm | Present — auto-positions patient; continuous monitoring | Absent | Reduces variability from patient positioning — beneficial for anxious patients |
| AI centration | Present — tracks micro-rotations in real time | Absent | Micro-rotations during lenticule creation are a known precision variable; AI compensation reduces this |
| Hyperopia treatment | CE-marked for hyperopia up to +6D | Not indicated for hyperopia | SMILE Pro treats a wider prescription range — relevant for patients with farsightedness |
Our guide on SMILE Pro vs SMILE corneal biomechanics covers the published structural data. For the safety comparison: is SMILE Pro safer than SMILE.
Who Is Best Suited for Each Procedure?
| Patient Profile | Better Choice | Why |
|---|---|---|
| Myopia -1D to -10D only | Either procedure equally | Both achieve 98–99% 20/20+ — comparable safety and outcomes for this prescription range |
| Hyperopia (+1D to +6D) | SMILE Pro only | ReLEx SMILE is not indicated for hyperopia — only SMILE Pro has the hyperopia CE mark |
| High-anxiety patients | SMILE Pro | 7–10 seconds vs 25–30 seconds; Smart Robotic Assistance reduces patient positioning anxiety |
| Contact sport / military aspirants | Either — SMILE Pro preferred | No flap in either; SMILE Pro’s AI centration may produce marginally more precise outcomes important for performance vision |
| Budget-sensitive patients | ReLEx SMILE | More established and typically lower cost; 12+ years of published data provide strong clinical reassurance |
| Patients seeking latest technology | SMILE Pro | VISUMAX 800 is the current generation — AI centration, robotic assistance, and hyperopia range are genuine advances |
For SMILE Pro’s full clinical advantages, see our guide on SMILE Pro eye surgery benefits.
Conclusion
SMILE Pro and ReLEx SMILE both deliver excellent flapless vision correction — 98–99% 20/20+ outcomes for myopia with either procedure. ReLEx SMILE: 12+ years of evidence, lower cost, still excellent. SMILE Pro: faster (7–10 sec vs 25–30 sec), lower suction loss, AI centration, robotic assistance, and hyperopia treatment. For myopia on a budget: ReLEx SMILE. For hyperopia, procedure speed, or the latest platform: SMILE Pro. Both available at Visual Aids Centre — the first SMILE Pro centre in Delhi.
Ready to find out which procedure matches your prescription? Book a candidacy assessment at Visual Aids Centre — every consultation includes a full refractive workup and procedure recommendation.
Frequently Asked Questions
What is the main difference between SMILE Pro and ReLEx SMILE?
The laser platform. SMILE Pro uses ZEISS VISUMAX 800 at 2 MHz — lenticule in 7–10 seconds. ReLEx SMILE uses VISUMAX 500 at 500 kHz — 25–30 seconds. SMILE Pro adds Smart Robotic Assistance and AI centration; ReLEx SMILE does not. Both flapless with comparable final visual outcomes — the difference is procedural precision, speed, and treatment range (SMILE Pro also treats hyperopia up to +6D).
Which gives better vision — SMILE Pro or ReLEx SMILE?
Final visual outcomes are comparable. Published clinical series report 98–99% of patients achieving 20/20 or better for myopia with both procedures — compared to 99.5% for Femto-LASIK (AAO 2024). SMILE Pro’s AI centration may offer marginally more consistent outcomes by reducing micro-rotations, but both deliver excellent final vision for eligible prescriptions.
Is SMILE Pro available for hyperopia?
Yes — SMILE Pro has CE-mark approval for hyperopia up to +6D. ReLEx SMILE is not indicated for hyperopia (FDA approved 2018 for myopia and myopic astigmatism only). If you have a farsighted prescription and want a flapless procedure, only SMILE Pro is an option.
Is ReLEx SMILE still a good choice in 2026?
Yes — 12+ years of published clinical data; FDA 2018 approval for myopia and myopic astigmatism; strong safety record. For myopia within the approved range, ReLEx SMILE remains clinically excellent. SMILE Pro offers procedural improvements — not necessarily better final vision for the same prescription range. Budget-conscious patients have strong published evidence supporting ReLEx SMILE.
Which is better for dry eye patients?
Both are significantly better than LASIK — neither creates a corneal flap, preserving substantially more of the subbasal corneal nerve plexus. Published PMC data (Fudan University EENT Hospital study) shows both SMILE variants produce significantly less post-operative dry eye than femto-LASIK (OSDI MD −4.82 at 3 months vs LASIK). Between the two SMILE variants, outcomes are comparable for dry eye.
